Security readout for executives and security teams
Plain-English summary
CVE-2021-47784 is a crash vulnerability in Cyberfox Web Browser 52.9.1, with possible impact to other versions. A very large search-bar input can make the application stop working. This affects availability of the browser, not data confidentiality or integrity based on the provided sources.
Executive priority
Treat as a legacy-browser cleanup issue unless Cyberfox supports critical operations. The main business risk is disruption from browser crashes. Prioritize inventory, removal, and replacement rather than emergency incident response, unless internal use is widespread.
Technical view
The issue is classified as CWE-770, uncontrolled resource allocation. The CVE record describes excessive data in the Cyberfox search bar causing an application denial of service. The supplied CVSS v3.1 score is 7.5, driven by availability impact. Public PoC information is referenced by Exploit-DB.
Likely exposure
Exposure is likely limited to endpoints where Cyberfox Web Browser is still installed, especially version 52.9.1. The source notes “possibly all versions,” but does not confirm a full affected-version range. Organizations not using Cyberfox are not directly exposed.
Exploitation context
A public Exploit-DB entry exists, but the bundle does not cite active exploitation and KEV is false. The described result is an application crash after processing excessive search-bar input. No evidence provided indicates code execution, privilege escalation, or data theft.
Researcher notes
Evidence is narrow: the CVE description and Exploit-DB reference describe a denial-of-service condition in Cyberfox 52.9.1. The affected range is uncertain because “possibly all versions” is not confirmed. No patch, fixed version, or active exploitation evidence is provided in the supplied sources.
Mitigation direction
- Inventory endpoints for Cyberfox Web Browser installations.
- Prioritize removal or replacement where Cyberfox is no longer required.
- Check Cyberfox/vendor guidance for any available fix or version-specific advice.
- Use application control to prevent unauthorized legacy browser use.
- Reduce business reliance on Cyberfox for critical workflows.
Validation and detection
- Confirm whether Cyberfox 52.9.1 is installed anywhere.
- Identify any other Cyberfox versions in use.
- Review endpoint software inventory and browser launch telemetry.
- Validate compensating controls block unmanaged legacy browsers.
- Document business owners for any remaining Cyberfox use.
Public sources used
Generated from the cited source records. This long-tail analysis has not been individually reviewed by a named human.
Conservative CVE-to-ATT&CK context
These mappings and lookup hints may be relevant to the vulnerability behavior, CWE, affected product, or exposure path. Glexia-inferred context is not an official MITRE, ATT&CK, CWE, or CVE Program mapping.
ATT&CK lookup starting points
Use these exact CWE pages and searches to review the Glexia ATT&CK library from this CVE's weakness and description context.
CWE-770: Exact CWE lookup
Use the exact CWE identifier as the starting point before reviewing related ATT&CK behavior. Open the exact CWE lookup page first, then review the ATT&CK searches from that MITRE weakness context. This is a Glexia lookup hint, not an official ATT&CK mapping.
Open ATT&CK lookupCVE-2021-47784 mapping review
Open the CVE-to-ATT&CK bridge for reviewed, inferred, or future official mappings tied to this CVE.
Open ATT&CK lookup- Severity
- High
- CVSS
- 7.5 (3.1)
- Known Exploited
- No
- Published
Vector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
CNA and ADP enrichment extracted from CVE v5
These fields come from the CVE record and ADP containers, not from Glexia's Take. They preserve time-varying source decisions such as CISA SSVC, KEV status, CVSS metrics, and provider references.
CVSS vector scores
1 official scoreWe collect every scored CVSS vector available in the official CNA and ADP containers. When more than one version is present, the table keeps the source vectors side by side instead of collapsing them into the highest score.
CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H3.93.6Primary CVE scoreVulnerability scoring details
Base CVSS 3.1 score
7.5HighVector: CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:N/I:N/A:H
Source materials
- CVE List V5 sourceCVE List V5
- ExploitDB-50336CVE reference · exploit
- Archived Cyberfox Web Browser HomepageCVE reference · product
Products and packages named in the record
CWE details
CWE links open Glexia weakness intelligence pages with official CWE context, developer remediation guidance, and related CVE mappings.
Allocation of Resources Without Limits or Throttling
Allocation of Resources Without Limits or Throttling represents a recurring weakness pattern that can create exploitable paths when design, validation, or implementation controls are missing.